Glaucoma is one of the major causes
of blindness. Glaucoma is a group of conditions, in which high pressure
inside the eye (intraocular pressure) damages the optic nerve of the
eye. Glaucoma usually affects both the eyes. It commonly occurs in
adults above 40 years of age, but can even occur in newborn babies. The
vision lost due to glaucoma is irreversible and can not be regained.
Hence it is very important to detect this disease as early as possible
and treat early to preserve vision.
What are the symptoms of open angle glaucoma in adults?
This form of glaucoma generally does not cause any symptoms in the
initial stages. The high pressure causes damage to the optic nerve and
leads to loss of peripheral visual field initially. Unless a routine
checkup is done, these changes go unnoticed and progressively lead to
further loss of visual field and the loss of central vision as well in
the later stages. Since this loss of vision is irreversible, glaucoma is
also called the 'silent killer'. Some patients may experience these
· Loss of peripheral vision: this is often not noticed until
considerable damage has occurred
· Blurred or foggy vision · Frequent change of glasses for
· Heaviness or dull pain in the eyes · Pain and redness of
· Halos or rainbow colored rings perceived around lights
What are the symptoms of glaucoma in children (congenital)?
The symptoms are redness, watering, photophobia (inability to tolerate
light), enlargement of the eyes, and corneal clouding. Glaucoma in
children needs to be managed very early and aggressively, in order to
save their vision.
is glaucoma diagnosed?
The aim of diagnosis in glaucoma is to diagnose the presence of the
condition, to determine the extent of the damage and to monitor the
progress of the damage due to the disease. There are various tests done
to measure the pressure (tonometry), look for the optic nerve changes
(fundus examination) and to document the visual field defects
(perimetry). The diagnosis is confirmed on basis of the clinical
condition and these findings. These special tests need to be repeated at
regular intervals to document the progression of the disease.
Can glaucoma occur at normal eye pressure also?
Yes. Each eye has different capacity for tolerating the pressure. What
may be normal for majority of eyes may be high for certain eyes. There
is a subtype of glaucoma called 'Normal Tension Glaucoma' in which the
eye pressure is apparently within the normal range, but still the optic
nerve gets damaged. Hence, presence of 'normal' pressure alone does not
rule out glaucoma. In suspected cases, one would like to do other tests
as well, even if the pressure is 'normal'.
What is the treatment of glaucoma?
The aim of the treatment is to preserve the visual function by
controlling the eye pressure (IOP) at the optimum level. The level of
IOP required (target pressure) depends upon the extent of damage and
other factors and is decided by the treating doctor. Medical treatment
is generally the first line of management. It includes eye drops and
tablets to control the pressure by either increasing the drainage or
decreasing the production of the fluid in the eye. These medicines are
generally to be used lifelong, and it is very important to use the
medicines regularly at prescribed timings and not to stop the medicines
without consulting the doctor.
Laser treatment is recommended in certain selected cases to create an
alternative pathway for the drainage of the fluid. Even after laser, a
few patients may still need to use medications to keep the pressure
under control. Surgery is recommended in cases where the medicines alone
are not effective or cause significant side effects. The surgery
increases the drainage of the fluid. Cryopexy or Cycloablation are used
in uncontrolled cases, and involve partial or total destruction of the
tissues that produce the fluid in the eye.
Why is early detection and treatment important?
The vision lost due to glaucoma can not be regained, even after the
surgery or other treatment. However a good control of eye pressure (IOP)
by the means described above can help in preserving the vision or in
minimizing the further damage. Hence it is very important to detect and
treat the disease at an early stage before it has caused significant
How can we detect glaucoma early?
Since this disease does not have any symptoms in the early stages, the
only way to detect it early is by doing regular eye checkups, especially
in those who are at a high risk for developing glaucoma.
What are the risk factors for glaucoma?
Glaucoma is more common in people above 40 years of age. Diabetes,
minus power of glasses, eye injury, eye surgery, long term use of
steroids tablets or drops, and a family history of glaucoma are other
important risk factors. Persons with any of these risk factors must get
regular eye checkups to detect glaucoma early.
Why is regular treatment and follow up important?
Even a single episode of high pressure can cause significant damage to
the eye. Hence it is very important to use the drops and medicines
regularly to control the pressure. The progression of the disease and
the vision loss is generally not detectable by the patient. It is
therefore necessary to maintain regular followups to document the change
in vision, optic nerve changes and field defect, and to modify the
treatment accordingly. For this purpose repeated tonometry, field
checkup (perimetry) and other special investigations may be required.
With the current treatments available, most of the patients maintaining
regular treatment and follow up would be able to preserve their useful
vision and can continue to lead a productive life.